Fuel injection pump



, Dec. 7, 1948. H. c;l EDWARDS FUEL inJEc'rIon wur Filed Nov. 11, 1944 3Sheets-Sheet l Dec. 7, 1948. H. C, EDWARDS 2,455,571

FUEL INJECTION Puur Dec. 7, 1948. H. c. EDWARDS FUEL INJEGTIOH PUMPFiled Nov.' 11, 1944 3 Sheets-Sheet 5 lllv me ff@ 1| Ill/f1 l, n

.f1/l5 HrroPA/EKS.

Pnenaa nee. 1, 194s l FUEL INJECTION PUMP Herbert- C. Edwards,Massillon, Ohio, assigner to The Tlmken Roller Bearing Company, Canton,4`Ohio, a corporation of Ohio Application November 11, 1944, Serial No.562,962

11 Claims. l

This invention relates to pumps. particularly single plunger fuelinjection pumps for multicylinder compression ignition engines. Theprincipal objects of the present invention are to provide a simple,economical and compact pump of the above type that will deliver acorrect quantity of fuel to each working cylinder of the engine inproper timed relation to the working cycle thereof; that will provide aunit injection and supply pump construction in which the supply pump isoperated by the injection pump; that will utilize the varying pressuredeveloped by the pump for automatically regulating the quantity and thetime of the fuel injection in accordance with the speed of the engine;that will provide for manually adjusting the timing ofthe fuelinjection; that will provide manually operable means for changing themaximum pressure of the fuel byl passed from the pump to set the pumpfor different engine speeds; and that will obtain other advantageshereinafter appearing. The invention consists in the single plunger,multiple discharge fuel injection pump and in the parts and combinationsand arrangements of parts hereinafter described and claimed.

In the accompanying drawings, which form part of this. specication andwherein like symbols refer to like parts wherever they occur,

Fig. l. is a central longitudinalsectional view of a fuel pump embodyingmy invention,

Fig. 2 is an end elevational view of the supply pump end of said fuelpump,

Fig. 3 is a, cross-sectional view on the line 2-3 in Fig. l,

Fig. i is a cross-sectional view on the line 4-4 in Fig. l.,

Fig. 5 is a cross-sectional view on the line E-- in Fig. l,

Fig. 6 is a central longitudinal section 'on the line 6 6 in Fig. 3, thefuel control sleeve being shown in no throttle position,`

Fig. 'l is a view similar to Fig. 6, showing the fuel control sleeve infull throttle position,

Fig. 8 is an enlarged fragmentary central longitudinal section throughthe fuel inlet end of the injection pump barrel,

l, Fig. 9 is a fragmentary sectional view similar to Fig. 5, showing thepump provided with means for manually changing they time of the fuelinjection,

Fig. 10 is a view similar to Fig. 9, showing the pump provided withmeans for hydraulically actuating the fuel timing mechanism; and

Fig. 11 is a fragmentary section on the line I I-I I in Fig. 3 showingthe manner in which the hydraulically operated fuel injection timingmeans is placed in communication with the supply pump for operation bythe pressure developed thereby.

The single plunger, multiple injection fuel pump shown in theaccompanying drawings is adapted for use with a six-cylinder, fourcycle, compression ignition engine. Said fuel injection pump comprisesan elongated housing or casing I having axially alined cylindrical endopenings 2 and 3, respectively, and a side opening 4 closed by aremovable cover plate 5. A drive shaft B extends into the housing Ithrough the end opening 2 thereof and is adapted to be driven by or inunison with the engine at one-half engine speed. The drive shaft 6 issupported in two rotary antifriction bearings 1 and B mountedrespectively in an annular end cap 9 for the end opening 2 of thehousing I and in a cross wall I formed in said housing intermediatebetween the ends thereof. The end cap 9 is removably secured to thehousing i by cap screws Ii and has a cylindrical plug portion 9a that tswithin the end opening 2 of said housing. A suitable oil seal ifsurrounds the drive shaft 6 and is supported in the opening providedtherefor in the annular end cap 9. f

Mounted in the end opening 2 of the housing I in endwise abuttingrelation to the inner end of the plug portion 9a of the annular endclosure 9 for said opening is an annular holder I3 which supports threevcircumferentially spaced conical cam rollers It that are disposedradially of said holder and taper inwardly towards the axis thereof. Thecorneal cam rollers It are located in pockets I5 provided therefor inthe annular holder I3 and are journaled on pins IB mounted in radialbores provided therefor in said holder. 'I'he annular roller holder I3is prevented from rotating with the drive shaft 6 by means of a dowelpin II which is fixed in the inner end of the plug portion 9a oftheannular end closure 9 and fits Within a radial slot I8 provided thereforin the adjacent end of said holder.

Mounted on the drive shaft 6 opposite the inner end of the fixed rollerholder I3 is an annular cam member I3 having a conical cam face 20 atThe drive shaft 6 has a tubular inner end portion Ba adapted to receivea fuel injection p ump plunger 24 which rotates with said tubular endportion but is reciprocable axially therein with the annular cam memberI9 spllned thereon. The reciprocating motion of the cam member i 9 isimparted to the plunger 24 through a transfer plate 25 which is locatedin the tubular portion 6a of the drive shaft 6 and has a T-slot 26adapted to rotatably receive the adjacent headed end 21 of said plungerand a lug28 lthat fits in a notch 2Ia in the internal rib or spline 2lin the drive shaft receiving bore of said cam member. The rotary driving`connection between the rotary but non-axially slidable drive shaft 8and the cam reciprocated pump plunger 24' comprises a lug 29 that isrigid with said plunger near the headed end 21 thereof and is slidabiein the longitudinal spline receiving slot 22 in the tu-'bular plungerreceiving inner end portion of said drive shaft.

The rotary` and reciprocable pump plunger 24 works in a pump cylinder orbarrel 30 having an enlarged intermediate portion 3| that nts the endopening 3 in the pump housing l and a larger head portion 32 that isdisposed in endwise abutting relation to the' outside face of saidhousing around said end opening. The plunger 24 cooperates with thebarrel 30 to form a pressure chamber or space 33 therein; and saidplunger has an axial bore 34 that extends from the working end thereofto a point beyond the inner end of the barrel 30 and communicates withand forms part of said pressure chamber or space. The plunger 24 has anexterior annular groove 35 formed therein adjacent to the blind end ofthe axial bore 34 thereof and-one or more radial pressure relief ports36 leading from said bore 'to said annular groove.

Slidable on the plunger 24 Ibetween the barrel 30 and the driving lug 29ls a fuel control sleeve 31 which is connected to said barrel by meansof an axially extensible sleeve 38 that cooperates with said controlsleeve, barrel and plunger to form therewith an -annular chamber 39 thatis adapted to be placed in communication with the exterior annulargroove 35 in said plunger through one or more radial ports 40 in saidcontrol sleeve. The extensible sleeve 38 preferably comprisesa length ofoil resistant rubber tubing containing a metallic coil springreinforcement 38a which resists radial expansion of said tubing whilepermitting axial elongation thereof by the pressure of the fuel in theannular chamber 39. The ends of the elastic sleeve 38 are secured to thebarrel 30 and to the control sleeve 31 preferably by means ofconventional hose clamps 4| which `provide leakproof connections[between said extensible sleeve and said barrel and control sleeve.` Ifdesired, the axially extensible sleeve 38 may be in the form of a,Sylphon bellows. y

The pump barrel 30 has the outer end of its plunger supporting boreenlarged to receive a high pressure double fuel inlet valveassemblyfthrough which fuel is supplied to the pressure space or chamber33. Said inlet valve construction comprises a cylindrical inner valvebody 42 and a cylindrical outer valve body 43 that is threaded into theenlarged outer end portion of the plunger receiving bore of the barrellmember and |bears against said inner valve, body and presses the latterendwise against a gasket 44` that seats against an annular shoulder 45provided therefor by the enlarged outer end portion of said bore. Theouter valve body 43 carries a packing ring 43a Awhich seals the jointbetween said body and the supporting bore therefor. The abutting ends ofthe inner and outer valve bodies are reducedto form with the enlargedouter end portion of the plunger supporting bore of the barrel-30 anannular fuel inlet chamber 48; and the head 32 of the barrel memberr hasa radial fuel passageway 41 leading from the outefi` periphery of saidhead to said annular fuel inlet chamber. The outer end of the innervalve body 42 has an annular groove formed therein that cooperates withthe,

adjacent inner end of the outer valve body 43 to form an annular valvechamber 48. The outer valve body 43 has a series of circumferentiallyspaced radial passageways 49 leading inwardly from the annular fuelinlet chamber 4'8 to an annular groove 50 formed in the inner end ofsaid valve body and opening into the annular valve chamber 48.

The annular valve chamber 48, in turn, opens through a circular seriesof longitudinal ports 5I in the inner valve body 42 into an annulargroove 52 in the inner end thereof. The annular groove 52 communicateswith the pressure space or chamber 33 in the pump barrel 3l! through awasher 53 which seats against an annular shoulder provided at the outerend of said chamber. As shown in the drawing, the washer 53 has acircular series of fuel ports 54 therein between the central openingtherethrough and the outer margin thereof. Located in the annular valvechamber 48 is an annular disk valve 55 which closes the annular groove58 in the outermost valve body 43 and is normally held in closedposition by means of a coil spring 58 interposed between said valve andthe inner end wall of said chamber. The annular groove 52 in the innerend of the innermost valve body 42 is closed by asimilar annular diskvalve 51 which is normally held in closed position Iby means of a coilspring 58 interposed between said valve and the washer. The washer 53has an outstanding flange 53a around the central opening therein, saidiiange and the small 'openings 54 in said washer tending to preventbroken valve spring parts from ventering the pressure chamber 33.

The pump barrel member 30 has a plurality of fuel discharge passageways59 therein, one for each of the six working cylinders of the enginesupplied by the pump. The fuel discharge passageways 59 are spaced apartequally about the axis of the barrel member 30 with their inner endsopening into the plunger supporting bore inwardly of the double inletIvalve construction and with their outer ends opening through the outerend face of the head 32 of said barrel member where they are threadedfor connection with injection lines or conduits (not shown) that lead tothe injection nozzles (not shown) for the respective working cylindersof the engine. Communication is established between the pressure spaceor chamber 33 and the several fuel discharge passageways through aradial port in the axial bore of the pump plunger 24.

The barrel or cylinder 30 o! the fuel injection pump is held in the endopening 3 of the ump housing I by means of an lend cap""or platy u6|which is secured by cap screws 62 to the adjacent end of said housingand has a'circular hole therethrough adapted to snugly receive thecylindrical head portion 32 of said pump barrel or cylinder. The hole inthe retaining plate or cap 6I has an annular lip or flange 63 at theouter end thereof that overlaps the head 32 of said barrel and retainsthe same in said hole. The head supporting opening in the retainingplate 6I is sealed against leakage by two sealing rings 64 locatedtherein one on each side of the radial fuel inlety passageway 41 in thebarrel head 32.

The pump chamber 33 is supplied with fuel by a supply pump mechanismoperated from thev drive shaft 9 of the fuel injection pump. This acrank 69 that operates in a recess 10 in the plate 6I and has a pin 1Ithat fits within a transverse opening provided therefor in the piston65, whereby said piston is adapted to be reciprocated when said shaft isoscillated. The inner end of the piston operating shaft 66 is supportedin a suitable anti-friction bearing 12 provided therefor in thetransverse wall I of the housing I; and said shaft is provided adjacentto said wall with a rocker lever 13 having a cam 'roller 1t journaled onthe free end thereof. The cam roller 'it cooperates with a hexagonaledge cam 15 which is nxed to the inner end of the drive shaft 6 forrotation therewith, whereby the rocker shaft 66 is osoillated by therotary movement of said drive shaft.

Fuel from a tank or other source of supply (not shown) is supplied to achamber 'I6 at one end of the piston supporting bore through a valvedinlet fitting 11 threaded therein. The fitting 11 is provided with aninlet valve comprising a disk cage. A coil spring 86 is interposedbetween the valve cage 69 and the opposing end of the piston B formoving said piston in one direction of its reciprocating movement. Thepiston 65 is moved in the other direction of its reciprocating movementby the hexagonal cam 15 on the inner end of the drive shaft 6.Continuous communication is provided between the chamber 8| and theradial fuel inlet passageway 41 in the pump barrel head 32 through afuel supply passageway 81 in the retaining plate 6I.

The chamber 16 formed between the inlet valve fitting 11 and theadjacent end of the piston 65 communicates with an outlet passageway 88which opens through the end cap 6| and is provided 6 with an outwardlyopening disk valve I9 which is held to its seat by means of a'spring 89.The chamber 8| formed between the inlet fitting 82 and the adjacent endof the piston 6I opens-into a by-pass passageway 9| having an outwardlyopening disk valve 92 therein that is held to its seat by means of aspring 98. The by-pass passageway 9| is provided with a threaded plug 96 having an axial recess therein for supporting the valve closing spring93. The threaded plug 6l has a throttle lever 96 xedto the exposed outerendthereof, whereby said plug may be rotated to vary the valve closingpressure of the valve spring 93. The passageway 8| communicatesoutwardly of the valve 92 therein through a passageway 91 with a fueloutlet opening 98. By this arrangement, the reciprocating movement ofthe fuel supply piston 65 causes oil to be drawn from the supply tankthrough the fitting 11 into the chamber 16, thence through the valvedpassageway B8 to a suitable filter (not shown), thence through the inletvalve fitting 82 to the chamber 3| and thence -through the supplypassageway 81 and double inlet valve to the pressure space 33 of thefuel injection pump for delivery through the fuel discharge passageways59 to the engine cylinders, the surplus fuel being returned to the fuelsupply tank through the bypass passageways 9|, 91 and 90.

The pump barrel member 30 has a longitudinal fuel passageway 99 thereinwhich opens at one end into the annular fuel chamber 39.formed by theextensible sleeve 30 and terminates at its outer end in a portion thatis disposed radially of said barrel member and opens through the outerperipheral face of the head portion 32 of said barrel member. The pumpbarrel retaining plate 0I has an opening |00 therein that is threaded toreceive a cap screw IllI which terminates at its inner end in a dowelplug |02 that nts within the radially disposed outer end portion 99a ofthe passageway 99 in the pump barrel member 30 and thus prevents saidmember from rotating. The fuel supply passageway B1, which leads fromthe supply pump chamber 8| to the radial fuel inlet passageway 41, isextended to communicate with the dowel screw receiving opening |00; andthe dowel screw i0| has a fuel passageway |03 therein that establishescommunication between said fuel supply passageway and the radiallydisposed cuter end portion of the fuel passageway 99 leading from the,axially expansible annular chamber 39 formed by the extensible sleeve38. The fuel .bypass passageway 99 also has a branch passageway 996intermediate between the ends thereof that ls disposed radially of thepump barrel 30 and opens into the pressure chamber or space 33 thereinadjacent to the double inlet valve end thereof.

Movement of the axially slidable fuel control sleeve 31 in the directionof the pump barrel 30 is limited by means of a stop screw |04 that isthreaded through a lug |05 provided therefor on the cross wall I0 of thehousing l and has an eccentric end portion |06 disposed in the path oftravel of an outstanding circumferential flange |01 on said sleeve. Byrotating the stop screw |04, the position of the eccentric stop pinportion |06 thereof may be changed to vary the travel of the controlsleeve 31 in the direction of the pump barrel 30.

The operation of the hereinbefore described pump is as follows: Thedrive shaft 6 is continuously rotated from the engine at one-half enginespeed and the fuel injection pump plunger 24 rotates withsaid driveshaft while being recip- 7 rocated in the pumpl barrel or cylinder 30 bythe roller actuated cam 19 splined on said shaft, the pump plungermaking one complete rotation for each engine cycle and the plungermaking six reciprocating cycles for each rotation that it makes. At thesame time, the crank shaft 36 is operated by the cam 16 on the driveshaft 6 to impart onecomplete reciprocating cycle to thc supply pumppiston 65 for each complete reciprocating cycle of the fuel injectionpump plunger 24. During this reciprocating movement of the s'upplylpumppiston 65, fuel from the supply tank is drawn through th'e valved inletfitting 11 into the primary fuel inlet chamber 16 at one end of y saidpiston and is forced through the valved outlet passageway 88 into thefilter and thence through the valved inlet fitting 82 into the secondaryfuel inlet chamber 8| at the opposite end of said piston. The fuel inthis secondary inlet chamber 8 I is then forced by the piston 65 throughthe inclined supply passageway 81 and through the radial fuel inletpassageway 41 in the pump barrel head 32 into the annularchamber 46,radial passageways 49 and annular groove 50 of the double fuel inletvalve assembly for the working chamber 33 of the fuel injection pump.

During the suction stroke of the injection pump plunger 24, the supplypump piston 95 produces enough pressure to lift the two high pressureinlet valves 55 and 51- oi their seats and fill the entire pressurespace or chamber 33 ofthe imection pump with fuel. During the forward orworking stroke of the pump plunger 24 part of the fuel drawn-into thepump chamber 33 flows into the overflow or by-pass passageway 99 untilthe branch 99h thereof is covered by the plunger; whereupon theremaining fuel trapped in said chamber is forced therefrom under highpressure through the radial discharge port 60 into one of the fueldischarge passageways 69 leading to the injection nozzle suppliedthereby. The fuel injection terminates when the radial port 36 in thepump plunger 24 registers with the radial pressure relief port 40 in thecontrol sleeve 31 and thus relieves the pressure in the pump chamber 33andl permits the inlet valves 55 and 51 to close. The excess fuel flowsthrough the radial ports 36 and 40 into the axially expansible chamber39 in the axially extensible sleeve 33 and thence through the passageway99 into the fuel supply passageway 81 to mix with the incoming fueltherein. During the reciprocating movement of the pump plunger 24, saidplunger is also rotated due to its connection with the continuouslyrotating drive shaft 6. Thus, the single fuel discharge port 60 in thepump plunger 24 successively registers with the six fuel dischargepassageways 59 in the pump cylinder, the injection plunger makingonecomplete reciprocating cycle for each injection and onecompleterotation for each complete engine cycle.

The fuel supply` pump has a certain overcapacity and thus delivers anexcess quantity of fuel to the secondary fuel chamber 8| of said pump, apredetermined pressure of such excess fuel in said chamber forcing thepressure relief valve 92 to lift off its seat and permit the surplusfuel to return to the supply tank through the passageways 9| and 91 andthe by-pass fuel outlet 98. The pressure relief valve 92 also opens torelieve the sudden pressure increase created in the by-pass system whenthe pressure space 33 of the injection pump is placed in communicationwith the axially expansible annular by-pass chamber 39 to terminate thedelivery of fuel through the 8 fuel discharge passageways 69. of theinjection pump. a 1

The quantity of fuel delivered to the engine through the dischargepassageways 59 depends uponn the axial position of adjustment of thefuel control sleeve 31 on the pump plunger 24. Thus,

sure relief port in the plunger registers with the port in said sleeveAat a point in the working stroke of the plunger that shortens the fuelinjection and decreases the quantity thereof. When the control sleeve 31is adjusted so that the pressure relief port 36 in the plunger 24 is incommunication with' the port 40 in the control sleeve during the entireworking stroke of said plunger, said sleeve is in no throttle positionand no fuel injection occurs. As shown in the drawings, full throttleposition of the control sleeve 31 is established/by the eccentric stoppin |05 of the screw |04.

The axial position of adjustment of the fuel quantity control sleeve 31is'determined by the length of the axially expansible actuating sleeve33 therefor; and the axial length of said expansible sleeve depends uponthe by-pass fuel pressure which, in turn, vis controlled by thespringloaded by-pass valve 92. When the control lever 96 is adjusted toincrease the spring loading on the valve 92, thel by-pass fuel pressureincreases and the sleeve 38 is extended to move the control sleeve 31 inthe direction of decreased fuel supply, thus decreasing the speed of theengine. When the control lever 96 is adjusted to decrease the springloading on the pressure control valve 92, the bypass fuel pressuredecreases and the sleeve 38 shortens and pulls the control sleeve 31 inthe direction -of increased fuel supply, thus increasing the Speed ofthe engine. ting of the control lever 96, the fuel control sleeve 31 isautomatically adjusted according to the speed and load conditions of theengine by the varying by-pass pressure in the axially expansiole andcontractible operating sleeve 38. Thus, when the speed of the engineincreases, there is an increase in by-pass fuel pressure which causesthe extensible sleeve 38 to lengthen and move the con-l trol sleeve 31in the direction of decreased fuel feed, and when the engine speeddecreases the bypass fuel pressure decreases and permits the extensiblesleeve to shorten and move the control sleeve in the direction ofincreased fuel feed. Upon a rise in by-pass fuel pressure suilicient toovercome the-spring loading of the valve 92, said valve lifts off itsseat and permits the excess pressure to be' dissipated through thepassageway 91 and outlet 98 to the fuel supply tank.

T'ne construction shown in Fig. 9 dispenses with the dowel pin I1, so asto permit rotation of the roller holder I3 in the supporting opening 2therefor in the housing I and provides means for circumferentiallyadjusting said roller holder relative to the cam I9 to advance or retardthe time of the fuel injection. The mechanism for circumferentiallyadjusting the roller holder I3 comprises a stud |08 which is fixed toand projects radially upwardly from the roller holder I3 through acircumferentially elongated slot |09 provided therefor in thecylindrical wall of the end opening 2 in which said roller holder isrotatably supported.

In each speed set-4 The stud Ill hasV a ball-shaped enlargement Illformed thereon near the upper end thereof that snugly fits in atranverse opening Illa provided therefor in a cross shaft III which issupported for axial sliding movement in alined holes II2 in the oppositeside walls of the housing I, the ends oi' the said transverse openingbeing flared to permit rocking movement of said stud therein. Theaxially movable cross shaft 'l l I is prevented from rotating by meansof a screw l I3 which is threaded into the housing l with its endlocated in a longitudinal groove l Il provided therefor in said shaft.

The cross shaft Ill has one end threaded and extended outside of thehousing I to receive the internally threaded hub portion IIEa of amanually operable lever l l5. I'he pump housing opposing end of the hubIllia of the lever IIE has an outstanding circumferential flange Ilbthereon which is held between 'the housing anda retaining,

plate I I6 that is screwed to said housing, thereby preventing axialmovement of said lever when the latter is rotated. By this arrangement,`when the lever IIB is rotated on the cross-shaft l I I, the threadedconnection between the hub of said lever and said cross-shaft causes thelatter to move axially in the supporting openings I|2 crosswise oftherotary axis of the roller holder I3. This endwise movement of thecross-shaft III forces the stud |08 to move therewith, thus rotating theroller holder I3 to change the 'circumferential position thereofrelative to the cam I9 and thereby advance or retard the time of thefuel injection relative to the engine cycle.

in Figs. 10 and 11, the pump is shown provided with a device whichutilizes the varying pressure developed by the fuel supply pump forautomatically regulating the time of the fuel injection in accordancewith the' speed of the engine. This hydraulically operated `timingdevice, like the manually operable timing device, comprises a stud itt,which extends radially upwardly from the rotatable roller holder I3through a circumferentially elongated slot |09 in the wall 'of theopening i in which said holder is supported, and a ball I I formed onsaid stud near the outer end thereof. In the construction shown in Figs.10 and 1l, the ball portion lill of the stud |09 snugly fits atransverse opening Illa through a cross-shatf ill which is supported foraxial sliding movement in openings I I8 provided therefor in theopposite side walls of the pump housing l. The shaft I I'I extends intoa cylinder IIS fixed to the outside iace of the adjacent side wall ofthe housing and terminates in an outwardly flanged end I2|I whichissoldered to and seals one end of a Sylphon bellows I2l whose oppositeend has an outstanding flange I22 that is clamped between the outer endof said cylinder and a closure cap |24 therefor which seals the otherend of 'said Sylphon bellows. A calibrated coil spring |25 is mountedaround the shaft between the inner end walls of the cylinder lit and theSylphon bellows l2l and serves to yieldably resist endwise expansionthereof.

Communication is establishedbetween the 4fuel supply pump and theSylphon bellows I2I through a passageway |26 that extendslongitudinallyof the adjacent side wall of the housing I and communicates at one endwith the outer end of the Sylphon bellows I2| .through a passageway I21`in the side wall of the cylinder and in the end cap |24 therefor. Theother end of the passageway |26 opens into the valved outlet passagewayB8 of the supply pump chamber 'IB outwardly of the outwardly openingdischarge valve 89 therefor. Throughout the speed range of the'fuelinjection pump, the supply pump is adapted to I pressure in the Sylphonbellows I2I operate tov hold the cross shaft Ill in the position of itsaxial adjustment that will maintain the fuel injection timing at themost eillcient point for the particular speed at which the engine isoperating. The cylinder Il8 is bolted against the lili main pump housingI with a gasket |28 interposed therebetween; and said cylinder isvented, as at |29 to permit free movement of the Sylphon bellows I2Itherein. `The fuel pressure, which is relatively high, is sealed withinthe passageways and the Sylphon valve without the use of sliding glands.

Obviously, the hereinbefore described fuel injection pump admits ofconsiderable modification without departing from the invention.Therefore, I do not wish to be limited to the precise arrangement shownand described.

What I claim is:

1. A fuel injection pump comprising a cylinder having a pump chamberwith a fuel inlet passageway and a fuel discharge passageway, a plungerreciprocable in said cylinder and forming therewith said pump chamber,said plunger having a fuel by-pass port in communication with said pumpchamber, said pump having a fuel by-pass conduit, a fuel control sleeveslidable on said plunger and having a fuel by-pass port in continuouscommunication with said ny-pass conduit and adapted to communicate withthe by-pass port of said plunger during the pressure stroke of thelatter, and means operable by variation in the. pressure of the fuel insaid 'by-pass conduit for shifting saidsleeve to bring the by-pass portthereof into successive communication with said fuel dischargepassageways and a second pump is provided for supplying fuel to saidinlet passageway and includes a piston that is reciprocated by theplunger rotating means.

3. The combination set forth in claim l in which the means forreciprocating said plunger comprises a drive shaft disposedin axialalinement therewith, a roller journaled on an axis disposed radially ofsaid shaft, a cam having an axially slidable but non-rotary connectionwith said shaft and movable by' said roller axially of said shaft toimpart the pressure stroke to said plunger, and means for adjusting saidroller circumferentially of said cam to vary the point in the rotarymovement thereof in which the pressure stroke is imparted to saidplunger by said cam.

4. The combination Iset forth in claim 1 in which said plunger has afuel discharge port in communication with said pump chamber and chargeport into communication with said fuel discharge passageway during thepressure stroke of said plungen/the means for reciprocating and rotatingsaid plunger comprises a drive shaft having an axially slidable drivingconnection therewith, a cam rotatable with and slidable axially ofsaid-shaft and operatively connected to said plunger to rotate andreciprocate the same, a stationary annular member surrounding saidshaft, a roller journaled in said annular member radially thereof, and aspring for holding said Acam in engagement with said roller, a secondpump is provided for supplying fuel to said inlet passageway, and saidannular member is rotatably -adjusted relative to said cam by variationin the pressure of the fuel in said second pump.

5. A .fuel injection pump comprising a cylinder having a pump chamberwith a fuel inlet passageway and a fuel discharge passageway. a plungerreciprocable in said cylinder and forming therewith said pump chamber, afuel control sleeve slidable on said plunger and having a fuel by-passport therein, and an axially extensible vsleeve surrounding said plungerwith one end fixed to said pump and the other end fixed to said fuelcontrol sleeve and forming an-axlally expan-sible and contractable fuelby-pass chamber, said control sleeve having a fuel by-pass port openinginto said by-pass chamber, said plunger having a fuel by-pass port incommunication with said pump chamber and adapted to register with saidcontrol sleeve by-pas-s port during the pressure stroke of said plunger,whereby variation in the pressure of the fuel in said by-pass chamberoperates to change the length of said sleeve and the axial position ofthe by-pass port therein relative to the by-pass port in said plunger tothereby vary the quantity of fuel delivered through said dischargepassageway.

6. The combination setV forth in claim vin which means is provided forvarying the maximum pressure of the fuel in said by-pass chamber.

7. A fuel injection pump comprising a cylinder having a fuel inletpassageway and a plurality of circumferentially spaced fuel dischargepassageways, a plunger reciprocable and rotatable in said cylinder andhaving a fuel discharge port adapted to successively register with saidfuel discharge passageways during the rotary movement of said plunger, ashaft disposed -in axial alinement with and operatively connected tosaid having an opening therein, a drive shaft journaled in said opening,a pump cylinder mounted in 'said housing in axial allnement with theinner end of said shaft and having fuel inlet and dis- 1 chargepassageways, a plunger reciprocable in said cylinder, a holder mountedin said opening, a roller journaled in said holder radially thereof, acam having an axially slidable driving connection with said shaft andcooperating with said roller for movement thereby axially of said shaft,a connection between said cam and said plunger, whereby the axialmovement of Isaid cam is imparted to said plunger, and means forrotating said holder in said opening to vary the point' in the rotarymovement of said cam in which said plunger is actuated thereby.

9. I'he combination set forth in claim 8 in which the means for rotatingsaid holder comprises a shaft vmounted in said housing cros'swi-se ofthe rotary axis of said holder, a stud projecting from said holder andoperatively connected to said shaft. and means for shifting said shaftaxially to actuate said stud.

10. The combination set forth in claim 8 in which the means for rotatingsaid holder comprises a shaft mounted in said housing crosswise of therotary axis of said holder, a stud projecting from said holder andoperatively connected to said shaft, and means responsive to variationin pressure of the fuel in said pump for shifting saidshaft axially toactuate said stud.

11. The combination set forth in claim .8- in 'which the means forrotating ysaid holder comprises a shaft mounted in said housingcrosswise of the rotary axis of said holder, a stud project'- ing fromsaid holder and operatively connected to said cross-shaft, and means forshifting said shaft axially to actuate said stud, said means comprisinga Sylphon bellows having one end fixed'and closed by one end of saidcross-shaft', a cylinder fixed to said housing and enclosing saidbellows and closing the other end thereof, and a spring for yieldablyresisting the expansive action of said Sylphon bellows, said housinghaving a fuelA conduit opening into said Sylphon bellows, whereby saidSylphon bellows is operable by variation in pressure of the 4fuel insaid conduit.

HERBERT C. EDWARDS.

REFERENCES CITED The following references are of record in the ille ofthis patent:

UNITED STATES PATENTS Number Name Date A1,978,480 Sevenson Oct. 30, 19342,142,086 Alden Jan. 3, 1939 2,147,390 Vandet Feb. 14, 1939 2,187,151Gillen Jan. 16, 1940 2,215,827 Ditto Sept. 24, 1940' 2,251,783 DavisAug. 5, 1941 2,265,232 Hoffer Dec. 9, 1941 2,280,875 Wahlmark 'Apr.l 28,1942 2,282,562 Cole L., May 12, 1942

